J. Nannoplankton Res. 27 (1), 2005, pp.1-14 © 2005 International Nannoplankton Association
ISSN 1210-8049 Printed by Cambridge University Press, UK

1

Living coccolithophores recorded during the onset of
upwelling conditions off Oman in the western Arabian Sea
Harald Andruleit*, Ulf Rogalla, Sabine Stäger
Bundesanstalt für Geowissenschaften und Rohstoffe (BGR), Stilleweg 2, 30655 Hannover, Germany; *h.andruleit@bgr.de
Manuscript received 2nd June, 2004; revised manuscript accepted 20th January, 2005

Abstract A transect off Oman was sampled in early June, 2000 at the onset of upwelling conditions in the northwestern Arabian Sea. Living coccolithophores were investigated in 21 samples from five stations with a scanningelectron microscope. From 77 identified taxa, several species contributed significant portions to the communities.
The overall dominant taxon was Gephyrocapsa oceanica, with an average 34%. Absolute abundances reach up to
more than 50 000 coccospheres per litre. Highest coccolithophore concentrations probably occur close to the
upwelling centres where oceanic and upwelled waters mix. Ecological preferences of several species are refined. G.
oceanica occurs with different morphotypes and has a preference for elevated nutrient levels. Additionally, thisspecies can cope with unstable surface-water conditions, that is, turbulent waters caused by active upwelling. In tropical regions, Emiliania huxleyi may not be regarded as an indicator of upwelling processes, but may be more typical of stable regimes in terms of vertical mixing with relatively high nutrient-availability. The occurrence of the subspecies Calcidiscus leptoporus ssp. quadriperforatus probably indicates early upwelling conditions. The deep-living
Florisphaera profunda plays only a minor role in the communities of the western Arabian Sea.

Keywords Arabian Sea, living coccolithophores, upwelling, ecology, environmental conditions

1. Introduction
We report a survey on living coccolithophores in the western part of the Arabian Sea, off the coast of Oman. The
samples were collected in early June, 2000 at the onset of
upwelling conditions and, therefore, comprise strongly
different environmental conditions and contrasting floral
assemblages. To date, only a few plankton studies havegiven information on the changing coccolithophore communities in the Arabian Sea, although Banse (1994)
recently proposed that coccolithophores might be themost important primary producers in this region. An
overview of species diversity and taxonomy was given by
Kleijne et al. (1989) and Kleijne (1991, 1992) for thesouthern Arabian Sea. A study of the central and northern
Arabian Sea was conducted by Guptha et al. (1995), whoinvestigated four stations on a south-north transect, reaching close to our studied area. Zeltner (2000) studied alarge number of water-samples from the northern Indian
Ocean and gave a comprehensive overview of the coccolithophore diversity. Further information was provided by
Andruleit et al. (2003), who investigated living coccolithophores in the northern Arabian Sea that were retrievedat the end of the summer (SW) monsoon in September,1993. The coccolithophore communities exhibited arather heterogeneous pattern in terms of species composition in surface-waters. Several species seemed to be able
to dominate the communities, but none of them had an
overall dominance (Andruleit et al., 2003). Recently,
Schiebel et al. (2004) studied the coccolithophore communities during the SW-monsoon in the Arabian Sea, incomparison with diatoms and planktonic foraminifers.

They proposed a coupling of nutrient concentration andcoccolithophore cell numbers with increasing coccolithophore numbers towards the open ocean, along withdecreasing nutrient concentration and increasing stratification of the upper water-column. An overview of coccolithophores in the Arabian Sea, in terms of their productionin the photic zone, transformation to settling assemblages,
accumulation on the sea-floor, and their final burial in thesediments, is provided by Andruleit et al. (in press). A
study on sediment-trap samples from the Somali Basin
showed that coccolithophores responded to seasonalchanges in monsoonal upwelling (Broerse et al., 2000).
Also, in the north-eastern Arabian Sea, a sediment-trap
study has revealed a strong relationship between the monsoon seasons and the seasonal flux of coccolithophores(Andruleit et al., 2000). For the present investigation, special emphasis was laid on the identification of species andspecies groups that are characteristic of upwelling conditions. The calibration of species-specific ecological tolerances is aimed at enhancing the potential of coccolithophores for palaeoceanographic reconstructions.
2. Environmental conditions
The Arabian Sea hydrography is controlled by the Indian
Ocean monsoon. Environmental gradients change distinctly between the SW-monsoon in summer (June to
September) and the NE-monsoon (December to February)
in winter. In summer, the steady and strong SW-monsoon
generates extensive coastal upwelling and eddy advection
over the continental margins, extending up to 400km seaward off the coast of Oman (Brock et al., 1992). In addi-

2Andruleit, Rogalla, Stäger

tion, open-ocean upwellingis induced due to Ekman
transport by strong windstress (Currie et al., 1973;
Brock et al., 1991). At theonset of the SW-monsoon,late in May/early June, due
to increasing wind-speeds,
upwelling centres originate
andspreadout.
Contemporaneously, phytoplankton growth increases due to the supply ofnutrients (Figure 1). Seasurface temperatures drop
significantly from >29°C
in the central Arabian Sea Figure 1: A) Wind and surface-water circulation and phytoplankton pigment concentration (modified afterin thedown to <20°C in the http://daac.gsfc.nasa.gov/CAMPAIGN_DOCS/OCDST/classic_scenes/04_classics_arabian.html)
Arabian Sea in early June, 2000 at the onset of upwelling conditions (large arrows = winds, small arrows =upwelling centres off currents). B) Bathymetry with location of samples
Oman (Currie et al., 1973;
2
Hastenrath & Lamb, 1979; Rixen et al., 2000). The cool- coccospheres, A = investigated filter area [mm ], and V =filteredvolume(l).
ing of the surface-water is attributed to upwelling (Rixen
For each sample, we applied the Shannon Information
et al., 2000). Environmental conditions during sampling
Functionas a reasonable measure of heterogeneity (diverare intimately connected with the occurrence of coccolsity).
Atonestation, diatoms greatly dominated the plankithophores and are presented in Section 4, ‘Results’.
ton communities. This qualitative observation was noted
and is commented on the text.
3. Material and methods
We performed a cluster analysis (centroid linkage
Plankton samples were collected during Marion Dufresne
method; distance metric is 1-Pearson Correlation
Cruise MD-117 in June, 2000 (Kissel & Schulz, 2000). In
Coefficient) on the relative abundances of species. Taxa
total, 21 samples from five stations were investigatedwith only sporadic occurrence and low cell-densities were(Table 1). Water-samples were taken at several depthexcluded.
intervals with a rosette sampler. Information about water
Digital images are archived in the BGR palaeontology
conditions were provided by CTD profiling, together withimage database. Stubs are stored in the BGR SEM collecfluorometer measurements (uncalibrated data).
tion.
Chlorophyll fluorescence serves as an indicator of phytoplankton concentrations, and thus provides a means ofassessing biological activity within the water-column. 4. Results
The water from each depth was filtered through fleece- 4.1 Physical data and diversity
supported, regenerated cellulose filters (Sartorius, Temperature and salinity data from all stations exhibited a
0.45µm pore-width) using a vacuum pump. Without fur- clear trend in surface-water conditions (Figure 2).
ther washing, rinsing or chemical conservation, the filters Warmest temperatures with highest salinities were foundwere dried in an oven at 40 to 50°C for at least four hours. at Station MD 2353. At southerly-located, and especially
The filters were then stored in plastic Petri dishes and kept more westerly-located, stations, surface-water temperadry with silica gel. Coccolithophore cell-densities were tures and salinities decreased significantly. Lowest values
determined with a scanning electron microscope (SEM), were reached at Station MD 2357. The top of the thermousually at 10kV. For that purpose, a small piece of the cline depth (defined as the depth where the temperature isdried filter was cut out, fixed on an SEM stub, and sput- 1°C cooler than at the sea-surface [Hastenrath & Merle,
tered with gold. The number of individuals and the 1987]) varied between about 20m to 40m. Fluorometer
species composition were determined by identifying and data underline the exceptional status of Station MD 2357,
counting coccospheres on measured transects at magnifi- with several times higher values than at the other stations.
cations of 2000x and/or 3000x. Generally, it was aimed to Similarly to the temperature and salinity values, the divercount 300 specimens. Cell-densities per litre of water sity (Shannon Function) of the coccolithophore communities decreased in a south-westerly direction and exhibited
were calculated as follows:
the lowest diversities at Station MD 2357.
F*C
Coccolithophore concentration (no./l) =-------- ,4.2 Coccolithophore data
A*V
2
where F = effective filtration area [mm ], C = number of A total of 77 taxa were identified in this study, with sev-

Water-depth: 3180m

25
50

MD 2354

08/06/00

21.043

Water-depth: 2740m

MD 2355

09/06/00

16.705

Water-depth: 2420m

MD 2356

10/06/00

16.123

Water-depth: 4020m

MD 2357

11/06/00

Water-depth: 345m

17.834

Count

Other

0
130

Holoc.

47

195 3445

3

Umb. spp.

3952

Syr. spp.

0

P. vand.

52

O. ant.

21.750G. ocea.

07/06/00

F. prof.

0

MD 2353

E. hux.

C. lept.
0

Datelong. (E)63.387 10

Stationlat. (N)Depth (m)Living coccolithophores recorded during the onset of upwelling

0 2496 2652

3172 3432

988 3234324

0799 2303

4183 2256 1504 331

5395

910

0 16900

325 9945 34280

051 1836

646

578

0

17

0

17

153 195

140

20

0

0

400

20

0

0

0

0

0

61.477 20

0

29

0

0

40

0

150

0

300

60

0

580

0

3335 20735

120

87

87 2407261

29 1682 1769
525

1682

3248 205922

841 335

450 2775 11925 3375 3825 311
145 7685 11455
0

725 8845 369

203

58

0 4234 311

0 1624 2494

59.711 25

0 1102

0

9860

3886

290 1856 370

38

0 2050

0

6100

1100

500 28500650 6150 389

70

294

504 6846

1260

4158

126

126

0

84 3570 405

90

0117 8463

546

2028

0

273

0

0 1170 329

60.759 30

0 12240 18564204

612 2652

4386 1836 4998 339

40

83 1079

83 12284

8881

332 2656

1328

83 6557 389

70

100

225 2300

1975

2075

0

175

0

0

800 310100

117

208 1456

1209

1131

0

65

0

0

195 338

57.393 10

5781

564

0 35391

1692

0

141

0

0 3243 332

30

5192

0

0 27848

1062

0

236

0

0 4012 325

40

6500

0

0 23600

800

0

0

0

0 1600 325

75

108

27

315

0

81

0

0

486

1557

351 316

Table 1: Locations of, and data for, the investigated water-samples. Species abundance = coccospheres per litre

eral species that contribute significant portions of thecommunities. Absolute abundances reach up to >50 000
coccospheres per litre at intermediate water-depths(Station MD 2354, 50m). The overall dominant taxon
was Gephyrocapsa oceanica, with an average 34%. This
species exhibited at least three different morphotypes,
with respect to different structures of the central area,
tube, and collar (Plate 1, Figures 1-3). Due to a high andvariable diversity, several species are not shown individually for the sake of clarity and comparability between thesamples. However, all taxa of importance for the aim of
this study (see Introduction) are either depicted on the figures or mentioned in the text. The genus Syracosphaera
consists of 19 species, but none of them had a clear dominance within this group. In contrast, Umbellosphaera
spp. comprises only the two species U. irregularis and U.
tenuis, with the former one as the dominant taxon of thisgenus in our samples. The holococcolithophore group isvery heterogeneous, with 20 different taxa, all with sporadic and mainly rather low occurrences. All identified
species are listed alphabetically, with full citations, inAppendix A (data are shown in Table 1). Selected taxa
are illustrated on the plates.
Results from all stations are briefly described below(Figure 3):

Station MD 2353: In the samples above the thermocline,
G. oceanica, Palusphaera vandelii, Syracosphaera spp.,
U. irregularis, U. tenuis and holococcolithophores contributed large proportions to the communities. Below thethermocline, solely at this station, Calciosolenia murrayi
occurred in high amounts. Cell-densities reach, at most,
22 000 coccospheres per litre at 50m water-depth.
Station MD 2354: Here again, P. vandelii, Syracosphaeraspp., Umbellosphaera spp. and holococcolithophores
contributed significantly to the communities, while G.
oceanica was absent in the upper water-column. Below
the thermocline, the highest cell-density of all samples,with 53 500 coccospheres per litre, was reached.
Especially Oolithotus antillarum occurred in high abundances at this depth. Similarly to Station MD 2353,
species of Syracosphaera spp. and Umbellosphaera spp.
were abundant, even below the thermocline. The sample
at 20m water-depth is the only one where U. tenuis dominates over U. irregularis.
Station MD 2355: At this station, G. oceanica was thedominant species in the upper water-column but also
other species contributed significantly. Below the thermocline, Florisphaera profunda and O. antillarum were themain components of the communities. Generally, intermediate to high cell-densities, between 10 000 and 20 000

4Andruleit, Rogalla, Stäger

further species could be
identified with indicative
abundance variations withrespect to the exceptional
environmental conditions.
Overall, cell-densities withup to 46 800 cells per litre
were high but not highest
when compared to the otherstations. In contrast to allother stations, diatoms
occurred in much higher
numbers
thancoccolithophores.
5. Interpretationand discussion
Temperature and salinity
data suggest that Stations
MD 2353 and MD 2354
were furthermost from the
upwelling centres. Stations
MD 2355 and MD 2356
seemed to be located closer
to the upwelling area,
whereas physical conditionsat Station MD 2357 indicate
a position at, or close to, theupwelling. The species composition and abundance of
coccolithophore communities support this classificaFigure 2: Shipboard-derived data of temperature, salinity and fluorometer units (Kissel & Schulz, 2000).
tion. Most coccolithophore
Additionally, the Shannon Information Function as a reasonable measure of heterogeneity (diversity) is
depicted
species tend to be more Kselected, and therefore arecells per litre, were reached at this station.
more
importantcomponentsof communities in warm,
Station MD 2356: The species compositions at this station
stratified,nutrient-poorwatersand less important in nutriwere rather similar to the ones found at Station MD 2355.
ent-richwaters(r-selected
species)(Brand, 1994; Young,
The main differences were due to somewhat higher total1994).
High
amountsofoceanic,
K-selected species
cell-densities in the upper water-column and lower ones
occurredinthesamplesat
Stations
MD
2353 and MD
below the thermocline.
2354
above
the
thermocline,
whilstr-selected
species
Station MD 2357: In all samples, G. oceanica was by far
wereabsentor
rare.
At
Stations
MD
2355
and
MD
2356,
the most abundant species, with more than 75% at 10m
similar
speciescompositions
were
observed,buttherwater-depth. Even in the deepest sample, at 75m waterselected
speciesG.
oceanica
wasalreadythedominant
depth, this taxon still dominated the community, whilst F.
profunda only contributed a minor proportion. The second species, and at Station MD 2357, this species dominatedmost abundant species was Calcidiscus leptoporus (Plate the communities by far. In consequence, the diversity
1, Figures 8, 9) that almost solely occurred at this station. (Shannon Function) decreased accordingly.
A repeated counting only of specimens of this species inthe sample from 10m revealed an overwhelming dominance of the subspecies C. leptoporus ssp. quadriperforatus (= C. leptoporus large), with more than 97%.
Interestingly, coccospheres of this species were often
found together (Plate 1, Figure 9), which possibly indicates a status of ongoing cell-division. Umbilicosphaera
foliosa was only found in rather low numbers at all stations, but had a slight maximum in the samples here. No

5.1 Ecological tolerances ofcoccolithophore species
Gephyrocapsa oceanica is known to represent high nutrient levels, especially in tropical to subtropical seas
(McIntyre & Bé, 1967; Okada & Honjo, 1977; Bollmann,
1997). Under the strong influence of monsoon climates,
this species is more abundant than any other placolithbearing coccolithophore species (Cheng & Wang, 1997;
Andruleit et al., 2000) and was even attributed to indicat-

Living coccolithophores recorded during the onset of upwelling

Figure 3: Coccolithophore data for the investigated sites, with profiles of temperature, salinity, and fluorometer units

5

6

Andruleit, Rogalla, Stäger

ing maximum upwelling conditions (Broerse et al., 2000).
Several studies in the Arabian Sea have confirmed thepreference of G. oceanica for elevated nutrient levels(Houghton & Guptha, 1991; Andruleit et al., 2000;
Broerse et al., 2000; Andruleit & Rogalla, 2002). The
present study additionally emphasises that G. oceanica
can cope with unstable surface-water conditions, i.e. turbulent waters caused by active upwelling. A cluster analysis underlines the exceptional status of this species(Figure 4). Together with Umbilicosphaera foliosa andFigure 4: Cluster analysis (centroid linkage method; distancemetric is 1-Pearson Correlation Coefficient) on the cell-densities of the most important taxa

Calcidiscus leptoporus, it forms a group with the greatest
distance from all other taxa.
C. leptoporus also contributed significantly to thecommunities in the upwelling area and appeared in thesame cluster as G. oceanica (Figure 4). This observationsuggests that, at least, the subspecies C. leptoporus ssp.
quadriperforatus (= C. leptoporus large) is not related tooligotrophic conditions. The use of C. leptoporus as anindicator of low nutrient levels, as still proposed by
Schiebel et al. (2004), has, therefore, to be questioned.
Already, a plankton analysis from the North Atlantic hasrevealed the affinity of large Calcidiscus cells with nutrient-rich conditions (Renaud & Klaas, 2001). Renaud et al.
(2002) showed that only the small and large morphotypes
occurred in the Arabian Sea, with the latter dominating
this genus. Also, other studies have suggested that
increased abundances of C. leptoporus may be indicativeof high productivity (Ziveri et al., 1995; Flores et al.,
1997; Kinkel et al., 2000; Henderiks & Renaud, 2004).
However, one has to bear in mind that the differentiationof all taxa within the genus of Calcidiscus is essential for
ecological specifications or usage as palaeoenvironmental
indicators. According to our study, the high abundance of
this species probably indicates early upwelling conditions. The common occurrence of C. leptoporus ssp.
quadriperforatus in the state of ongoing cell-division
probably indicates rapid and ongoing reproduction of thisspecies during this stage.
According to Young (1994), C. leptoporus, G. oceanica and, additionally, U. foliosa belong to the placolith-bearing coccolithophores which superficially may exhibit
an erratic biogeographical distribution worldwide, but all
typical environments exhibit similar ecological conditionsin that they are all eutrophic. The present study provides
strong evidence that all three species are indicators ofnutrient-rich conditions.
The species Florisphaera profunda and, especially,
Gladiolithus flabellatus played only a minor role in thecommunities of the western Arabian Sea. This agrees wellwith the finding of Andruleit & Rogalla (2002), that F.
profunda has a positive correspondence to the mixedlayer depth which is shallowest in the study region anddeepens to the east and south. The occurrence of both
species in one cluster indicates similar ecologicaldemands. A wide range of different conditions may control the occurrence and abundance of F. profunda (Jordan,
2002). Our study underlines the common thread that it isan indicator of low productivity in surface-waters.
Taxa such as Umbellosphaera spp. or holococcolithophores have been found to be negatively correlated to
upwelling conditions (Kleijne, 1991). Their occurrence isusually confined to stable, open-ocean conditions above
the thermocline (Kleijne et al. 1989, 1993; Andruleit etal., 2003). In our study, these species were found below
the thermocline, too. This observation may be explainedby instabilities in the water stratification due to the onsetof upwelling. In corroboration, F. profunda rarely dominated the communities below the thermocline. Since
Palusphaera vandelii clustered together with
Umbellosphaera spp., similar ecological tolerances may
be deduced.
Although Emiliania huxleyi is the most ubiquitous
coccolithophore species in the world ocean (McIntyre &Bé, 1967; Winter & Siesser, 1994) and is able to form
strong blooms (Holligan et al., 1983; 1993), it was notfound to dominate the communities in the northern
Arabian Sea. Generally, the distribution of this species
was found to be largely independent of water temperatureand thermocline depth (Samtleben et al., 1995a, b), andcells become very abundant in a nutrient-rich environment, such as along the edges of the subtropical gyres oralong the outer continental shelves (Brand, 1994). In
equatorial regions, however, this species may not be
regarded as an indicator of upwelling processes, but may
be more typical of stable régimes in terms of vertical mixing with relatively high nutrient-availability (Lampert etal., 2002). In more temperate regions, the ubiquitous E.
huxleyi seems to be more successful and outnumbers G.
oceanica even in upwelling areas (Mitchell-Innes &Winter, 1987; Giraudeau & Bailey, 1995). The co-occurrence of Umbilicosphaera sibogae in the same cluster(Figure 4) as E. huxleyi indicates some correspondence inthe ecological demands of the two species. Furthermore,
the taxa U. sibogae and U. foliosa, which were recently
emended into separated species according to molecular
genetic data (Young et al., 2003), indeed seem to inhabit
different ecological niches.

Living coccolithophores recorded during the onset of upwelling

Although other phytoplankton were not the focus of
this study, the high numbers of diatoms, together with thefluorometer data, clearly indicate that, at Station MD
2357, coccolithophores were not the dominant group.
Despite much higher chlorophyll concentrations than at
the other stations, coccolithophore abundances remainrather constant. Diatom numbers seem to be positively
related to nutrient concentration and negatively related to
coccolithophore abundances, while coccolithophore numbers increased towards more nutrient-depleted and stratified surface-waters (Schiebel et al., 2004). A dominanceof coccolithophores might be restricted to environmental
settings where biological conditions allow chlorophyllmaxima only at greater depth (Winter et al., 1994). Thisobservation indicates that coccolithophores are generally
K-selected taxa in relation to other phytoplankton groups.
Exceptions are the taxa G. oceanica and C. leptoporus
ssp. quadriperforatus, which appear to be more r-selected. According to the fluorometer profiles, it appears likely that, at the stations remote from the upwelling area,

turbulence

7al., in press).
6. Conclusions
Absolute coccolithophore abundances range from 10 000
to >50 000 coccospheres per litre in the upper water-column. Highest coccolithophore concentrations probably
occur close to the upwelling centres where oceanic andupwelled water mix. A total of 77 taxa were identified inthis study, with several species that contribute significant
portions to the communities. The overall dominant taxon
was Gephyrocapsa oceanica, with an average 34%.
We conclude that G. oceanica has a preference for elevated nutrient levels and, additionally, can cope withunstable surface-water conditions, i.e. turbulent waters
caused by active upwelling. The occurrence of the subspecies Calcidiscus leptoporus ssp. quadriperforatus (C.
leptoporus large) probably indicates early upwelling conditions. In equatorial regions, Emiliania huxleyi may not
be regarded as an indicator of upwelling processes, but
appears to be more typical for stable regimes in terms ofvertical mixing with relatively high nutrientavailability. The deep-living Florisphaera
profunda played only a minor role in the communities of the western Arabian Sea, emphasising the common thread that it is an indicator of low productivity in surface-waters.
High amounts of diatoms outnumbered coccolithophores at, or in close proximity to,active upwelling. This underlines that coccolithophores are generally K-selected taxa in
relation to other phytoplankton.
Acknowledgements

Figure 5: Schematic coccolithophore succession (diatoms are shown in addition)
on a schematic transect through the upwelling area perpendicular to the coast of
Oman. Modified after Zeltner (2000) and references thereincoccolithophore communities composed of taxa such as P.
vandelii, U. irregularis and U. tenuis had a greater portionof the phytoplankton biomass. Highest coccolithophore
concentrations probably occur close to the upwelling centres where oceanic and upwelled water mix (Giraudeau &Bailey, 1995). Generally, the results of our study support
the findings of Zeltner (2000), concerning the coccolithophore succession on a schematic transect through the
upwelling area off Oman (Figure 5). However, the overall
contribution of coccolithophores to phytoplankton abundance and biomass is rather low in the Arabian Sea. The
phytoplankton community structure is dominated byprokaryote taxa and only diatoms are sometimes able tocontribute significantly to phytoplankton standing stocks(Tarran et al., 1999). Although coccolithophores might
not be among the most important phytoplankton constituents in the Arabian Sea, their fossil record bears
unique potential for successful monitoring and reconstruction of palaeoenvironmental changes (Andruleit et

We thank the masters and crew of Marion Dufresne
Cruise MD-117 for their help in retrieving theplankton samples. The constructive criticism andvaluable comments of Karl-Heinz Baumann and
José-Abel Flores are thankfully acknowledged.

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Appendix A: Taxonomic list
The taxonomic list includes all taxa identified during the present
study. Identification followed Young et al. (2003) and Kleijne(1993), in which full references can be found.
Acanthoica quattrospina Lohmann, 1903
Algirosphaera robusta (Lohmann, 1902) Norris, 1984
Alisphaera extenta Kleijne et al., 2002
Alisphaera gaudii Kleijne et al., 2002
Alisphaera ordinata (Kamptner, 1941) Heimdal, 1973
Alisphaera pinnigera (Kleijne et al., 2002)
Alveosphaera bimurata (Okada & McIntyre, 1977) Jordan &Young, 1990
Anthosphaera lafourcadii (Lecal, 1967) Kleijne, 1991
Calcidiscus leptoporus (Murray & Blackman, 1898) Loeblich &Tappan, 1978
Calcidiscus leptoporus ssp. quadriperforatus (Kamptner, 1937)
Geisen et al., 2002 (= C. leptoporus large)
Calciopappus rigidus Heimdal in Heimdal & Gaarder, 1981
Calciosolenia brasiliensis (Lohmann, 1919) Young in Young etal., 2003
Calciosolenia murrayi Gran, 1912
Calyptrolithina divergens (Halldal & Markali, 1955) Heimdal,
1982
Calyptrolithina multipora (Gaarder in Heimdal & Gaarder,
1980) Norris, 1985
Calyptrolithophora papillifera (Halldal, 1953) Heimdal in
Heimdal & Gaarder, 1980
Calyptrosphaera oblonga Lohmann, 1902

9

Corisphaera gracilis Kamptner, 1937
Coronosphaera mediterranea (Lohmann, 1902) Gaarder in
Gaarder & Heimdal, 1977
Cyrtosphaera lecaliae Kleijne, 1992
Discosphaera tubifera (Murray & Blackman, 1898) Ostenfeld,
1900
Emiliania huxleyi (Lohmann, 1902) Hay & Mohler, 1967
Florisphaera profunda Okada & Honjo, 1973
Gephyrocapsa ericsonii McIntyre & Bé, 1967
Gephyrocapsa oceanica Kamptner, 1943
Gephyrocapsa? sp. type A sensu Kleijne, 1993
Gladiolithus flabellatus (Halldal & Markali, 1955) Jordan &Chamberlain, 1993
Heladosphaera cornifera (Schiller, 1913) Kamptner, 1937
Helicosphaera carteri (Wallich, 1877) Kamptner, 1954
Homozygosphaera triarcha Halldal & Markali, 1955
Michaelsarsia adriaticus (Schiller, 1914) Manton et al., 1984
Michelsarsia elegans Gran, 1912 emend. Manton et al., 1984
Oolithotus antillarum (Cohen, 1964) Reinhardt in Cohen &Reinhardt, 1968
Oolithotus fragilis (Lohmann, 1912) Martini & Müller, 1972
Ophiaster hydroideus (Lohmann, 1903) Lohmann, 1913 emend.
Manton & Oates, 1983
Palusphaera vandelii Lecal, 1965 emend. Norris, 1984
Pappomonas sp. type 2 Cros & Fortuño, 2002
Papposphaera lepida Tangen, 1972
Papposphaera sp. Tangen, 1972
Polycrater galapagensis Manton & Oates, 1980
Poricalyptra aurisinae (Kamptner, 1941) Kleijne, 1991
Poricalyptra magnaghii (Borsetti & Cati, 1976) Kleijne, 1991
Reticulofenestra sessilis (Lohmann, 1912) Jordan & Young,1990
Rhabdosphaera clavigera Murray & Blackman, 1898
Sphaerocalyptra adenensis Kleijne, 1991
Sphaerocalyptra quadridentata (Schiller, 1939) Deflandre, 1952
Syracolithus catilliferus (Kamptner, 1937) Loeblich & Tappan,
1963
Syracolithus dalmaticus (Kamptner, 1927) Deflandre, 1952
Syracolithus sp. Deflandre, 1952
Syracosphaera anthos (Lohmann, 1912) Jordan & Young, 1990
Syracosphaera corolla Lecal, 1966
Syracosphaera delicata Cros et al., 2000
Syracosphaera dilata Jordan et al., 1993
Syracosphaera epigrosa Okada & McIntyre, 1977
Syracosphaera florida Sánchez-Suárez, 1990
Syracosphaera halldalii Gaarder in Gaarder & Hasle, 1971 ex
Jordan & Green, 1994
Syracosphaera histrica Kamptner, 1941
Syracosphaera lamina Lecal-Schlauder, 1951
Syracosphaera marginaporata Knappertsbusch, 1993
Syracosphaera molischii Schiller, 1925
Syracosphaera nana (Kamptner, 1941) Okada & McIntyre,
1977
Syracosphaera nodosa Kamptner, 1941
Syracosphaera orbiculus Okada & McIntyre, 1977
Syracosphaera ossa (Lecal, 1966) Loeblich & Tappan, 1968
Syracosphaera pirus Halldal & Markali, 1955
Syracosphaera prolongata Gran, 1912 ex Lohmann, 1913
Syracosphaera pulchra Lohmann, 1902
Syracosphaera rotula Okada & McIntyre, 1977
Turrilithus latericioides Jordan et al., 1991
Umbellosphaera irregularis Paasche in Markali & Paasche,
1955

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Umbellosphaera tenuis (Kamptner, 1937) Paasche in Markali &Paasche, 1955
Umbilicosphaera anulus (Lecal, 1967) Young & Geisen in
Young et al., 2003
Umbilicosphaera foliosa (Kamptner, 1963) Geisen in Sáez etal., 2003
Umbilicosphaera hulburtiana Gaarder, 1970
Umbilicosphaera sibogae (Weber-Van Bosse, 1901) Gaarder,
1970
Zygosphaera bannockii (Borsetti & Cati, 1976) Heimdal, 1982
Zygosphaera marsilii (Borsetti & Cati, 1976) Heimdal, 1982

Plate 1
1: Morphotype of Gephyrocapsa oceanica with a delicate bridge and a large central-opening filled with a well-developed grille(Image # 2224; MD 2355, 90m)
2: Morphotype of Gephyrocapsa oceanica with a stronger bridge and a small central-opening (compared to morphotype of Figure1) with marginal pores (Image # 2301; MD 2357, 10m)
3: Coccospheres of Gephyrocapsa oceanica with a strong bridge, a large central-opening, and a prominent tube and collar. The coccospheres seem to be multilayered with only loosely-attached coccoliths (Image # 2542; MD 2356, 30m)
4: Intact coccosphere of Umbilicosphaera hulburtiana (Image # 2509; MD 2356, 30m)
5: Partially-broken coccosphere of Umbilicosphaera sibogae (Image # 2821; MD 2355, 25m)
6: Two coccospheres of Umbilicosphaera foliosa (Image # 2433; MD 2355, 38m)
7: Coccosphere of Emiliania huxleyi (Image # 2543; MD 2356, 30m)
8: Calcidiscus leptoporus small (Image # 2259; MD 2355, 90m)
9: Two specimens of Calcidiscus leptoporus ssp. quadriperforatus (= C. leptoporus large), probably in a status just after cell division (Image # 2320; MD 2357, 10m)
10: Morphotype of Florisphaera profunda with short coccoliths (Image # 2387; MD 2355, 90m)
11: Morphotype of a rosette-like coccosphere of Florisphaera profunda with elongate coccoliths (Image # 2390; MD 2355, 90m)
12: Two well-preserved coccospheres of Alisphaera unicornis (Image # 2432; MD 2355, 38m)

Living coccolithophores recorded during the onset of upwelling

Plate 1
Scale-bars = 3µm

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Andruleit, Rogalla, Stäger

Plate 2
1: Intact coccosphere of Rhabdosphaera clavigera (Image # 2806; MD 2355, 25m)
2: Coccosphere of Michaelsarsia adriaticus with only partially-damaged apparatus of circumflagellar coccoliths (Image # 2212;
MD 2354, 60m)
3: Coccosphere of Calciopappus rigidus with streamlined circumflagellar coccoliths. Several coccospheres exhibited such behaviour, supporting the idea of the flotation-related function of coccoliths (Young, 1994) (Image # 2420; MD 2355, 38m)
4: Only partially-broken coccosphere of the delicate species Palusphaera vandelii (Image # 2425; MD 2355, 38m)
5: Coccosphere of Calciopappus rigidus with normal (cf. Figure 3) shape of circumflagellar coccoliths (Image # 2524; MD 2356,
30m)
6: Calciopappus rigidus. Magnified sector of Figure 5 (Image # 2525; MD 2356, 30m)
7: Intact coccosphere of Umbellosphaera irregularis (Image # 2089; MD 2353, 25m)
8: Intact coccosphere of Umbellosphaera tenuis (Image # 2573; MD 2354, 20m)
9: Intact coccosphere of Syracosphaera pulchra (Image # 2093; MD 2353, 25m)
10: Intact coccosphere of Syracosphaera ossa (Image # 2016; MD 2353, 50m)
11: Intact coccosphere of Coronosphaera mediterranea (Image # 2080; MD 2353, 25m)
12: Partially-damaged coccosphere of Syracosphaera prolongata (Image # 2517; MD 2356, 30m)

Plate 3
1: Magnified part of Calciosolenia murrayi, showing body coccoliths (cf. Figures 2 and 3) (Image # 2033; MD 2353, 50m)
2: Magnified part of Calciosolenia brasiliensis, showing body (left) and apical (right) coccoliths (cf. Figures 1 and 3) (Image #2036; MD 2353, 50m)
3: Coccospheres of Calciosolenia murrayi (top left) and Calciosolenia brasiliensis (centre). The differences in size and shape ofthe coccospheres are obvious (Image # 2034; MD 2353, 50m)
4: Well-preserved coccosphere of Alveosphaera bimurata (Image # 2217; MD 2355, 90m)
5: Magnified section of Syracosphaera pirus (cf. Figure 6) (Image # 2107; MD 2353, 25m)
6: Collapsed coccosphere of Syracosphaera pirus (cf. Figure 5) (Image # 2106; MD 2353, 25m)
7: Intact coccosphere of Helicosphaera carteri var. carteri (Image # 2557; MD 2354, 20m)
8: Intact coccosphere of Homozygosphaera triarcha (Image # 2099; MD 2353, 25m)
9: Intact coccosphere of Discosphaera tubifera (Image # 2540; MD 2356, 30m)
10: Intact coccosphere of Poricalyptra aurisinae (Image # 2696; MD 2354, 40m)
11: Intact coccosphere of Calyptrolithina multipora (Image # 2568; MD 2354, 20m)
12: Intact coccosphere of Calyptrosphaera oblonga (Image # 2571; MD 2354, 20m)

Living coccolithophores recorded during the onset of upwelling

Plate 2
Scale-bars = 3µm

13

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Andruleit, Rogalla, Stäger

Plate 3
Scale-bars = 3µm